On Blanket Bog: Peat Restoration on Dartmoor's Uplands
“We’ve got really ambitious targets for Dartmoor ...”
Peat is in the news: for its ability to store vast amounts of carbon, its specialised communities of mosses, plants and invertebrates, and in stories of restoration, where research and hard work are helping to bring peatlands back to health. Today, in drenching cloud and cold wind, Rob and I are in north Dartmoor to walk across blanket bog and see for ourselves where restoration is taking place.
Peat has formed here over several thousand years. Where it’s healthy it may be up to 6 metres deep. But like peatlands across the UK and around the world, it is now badly degraded, and this degradation means more carbon is being leached into the atmosphere, instead of being stored, and many species relying on crucial wetland habitats are at risk. Research by the University of Exeter suggests that ‘just 1% of Dartmoor’s peatland area is still intact, healthy peat-forming bog, whilst lots of the remainder has been severely damaged by drainage, cutting, drying and erosion.’ Restoration is hugely important.
Pools forming in areas where the peat has been degraded. A series of ‘bunds’ helps to hold water in place, and this will help to create good conditions for sphagnum moss.
Restoration on the Forest of Dartmoor
We’re on a stretch of land called Ockerton Court with David Leach, project officer for South West Peatland Partnership. Lucky for us he has a very good digital map: in thick cloud, we can’t see further than 30 metres in any direction. The map shows us where we are and gives information about the peat. It shows where peat was cut in strips in the Mediaeval and post-Mediaeval years, mostly for domestic fuel; where gullies have formed to leave deep clefts; and where there is ‘dendritic’ erosion - pools, channels and tunnels where peat has eroded over time. Peat may also begin to dry when vegetation is burned. When peat is cut or dried, it releases greenhouse gases into the air. To stay healthy and store carbon, peat needs to stay wet, and coated with moss.
Some damage comes from long-ago cuts made for domestic use; some from previous tin mining; and here on Ministry of Defence land, the explosion of ordnance during army training and target practice has taken its toll. Ordnance explosion no longer occurs, but the craters and dips in the land are clear to see today.
Ockerton Court is on the Forest of Dartmoor, which is the biggest of the National Park’s commons. This area of restoration is around 95 hectares, a small segment of Dartmoor’s more than 300 square kilometres of upland peat (an estimated 175 square km of peat that’s more than 40cm deep, and 140 square km that’s less than 40 cm deep). After trudging across the boggy land, buffeted by wind, we take shelter between two idle diggers and David talks about the task at hand: first mapping the peatlands to record different levels of degradation, and then working with contractors to use the most appropriate techniques.
‘We’re putting in bunds, made out of peat, to hold the water in and to raise the water level. If you’re on deep peat and the peat is in reasonably good condition, it can be very quick indeed. In terms of holding the water up and creating a new habitat, it can be instantaneous. If you come back here in June or July, the pools may already be full of invertebrates.’
“We’re putting in bunds, made out of peat, to hold the water in and to raise the water level. If you’re on deep peat and the peat is in reasonably good condition, it can be very quick indeed. In terms of holding the water up and creating a new habitat, it can be instantaneous. If you come back here in June or July, the pools may already be full of invertebrates.”
The process of change
It’s exciting to hear just how quickly change can come about. Wading birds that rely on healthy blanket bog habitats for nesting are in decline but one species, the Dunlin, is still hanging on in Dartmoor. One of the sites where restoration work took place recently was known to be a nesting site for dunlins; David and his team have already seen an increase in Dunlin numbers. ‘That makes sense,’ he says, ‘because they’re after pools that are easily accessible for them and their chicks to get invertebrate food.’ And in these shallow pools, sphagnum moss, which is the key ingredient for peat formation, can begin to spread within a year of restoration work.
It’s not all that quick though. ‘Where gullies are too deep to block up with peat, we use peat and timber dams,’ David tells us. ‘In some places where the peat is very badly damaged and shallow, we’re going to do there is try and establish a little bit of willow to slow the flow of water. In other places, we’re using rolls of sheep fleece to create watertight blocks.’
The specialist diggers that are used put very little pressure on the ground, and are able to turn their buckets through 360-degrees so that peat can be moved without the whole machine moving. These vehicles, like the contractors who have the skills to work them, are in short supply. Given the amount of peatland areas requiring restoration around the UK (including in Yorkshire which we visited with Manon Pue last year), more people and equipment are needed. ‘We’ve got really ambitious targets for Dartmoor,’ says David. Finding the resources comes down to money, and political will, however. David reflects on the stark difference between levels of funding offered after the Second World War, and now: both times when massive change is needed.
‘After the war, there were armies of farm advisors going out asking farmers to pull out the orchard, pull out the hedgerow, grub up woodland, drain wetland. There were publicly funded agricultural colleges to train them to do that. And that's the culture that was developed in farming. Now that we realise this has caused us some problems, we try to make change on a shoestring.’
Not having enough targeted funding is a challenge that is mentioned by everyone we speak to as part of this project. Despite the pressing need to slow the emission of greenhouse gases, draw carbon from the atmosphere, and restore habitats for species in decline, the amount of government money being offered to support change is relatively small, and there is still a lack of clarity about how farmers will be funded so they can be part of this change. ‘The farmers and the commoners who work up here need to make a living out of providing public goods,’ says David, referring to the ‘public money for public goods’ commitment from Defra. ‘If they can't do that, then that farming culture will change, and I think that would be a real shame. Lots of the areas that we think of as natural in the UK are cultural landscapes, and if we lose the culture, we've lost something valuable.’
There’s also the question of priorities given to protecting precious habitats across England. ‘Biodiversity is declining across our whole landscape, including National Parks,’ says David. ‘National parks are supposed to be the finest landscapes that we have in this country - we need to do something to make sure that they are the finest landscapes and not the dangerously depleted habitats that they've become.’
“National parks are supposed to be the finest landscapes that we have in this country - we need to do something to make sure that they are the finest landscapes and not the dangerously depleted habitats that they’ve become.”
From uplands to lowlands
We bring the conversation back to the bog beneath our feet, and the challenge of walking here. It’s not easy. We stumble through knee-high Molinia (purple moor grass), and you never know how wet the ground will be when your foot lands, so we take it slowly. David shows us where diggers have formed bunds to create conditions that allow sphagnum moss to form. As the ground becomes saturated throughout the year, it no longer supports purple moor grass, heather, or other plants: more sphagnum moss can form, and the peatland can recover. Studies by researchers at Plymouth University observing the changes in areas of restoration have measured a significant shift away from purple moor grass monocultures to more varied vegetation communities within a decade. Change, it seems, is relatively quick, and it’s encouraging.
Given the global concern around carbon emissions and climate change, projects like this feel incredibly important. They are not, however, without controversy, and need to be planned in consultation. ‘We couldn’t have done this work here without the input of the Chair and the secretary of the Forest’s Commoners Association,’ says David, ‘or without the input from the archaeologists.’
Understanding more about how peat functions and can exist alongside other landscape uses - be these grazing, MoD defence training, or access for walkers - is part of the bigger picture of care for the uplands. And it’s worth remembering that when peat is restored, it’s not just the carbon storage or renewed habitats that are valuable: as more water is held up on the top of hills, whether in Cumbria, Yorkshire or Dartmoor, there’s less water travelling down to towns and villages below, and less chance of flooding when the heavy rains come. Sometimes the upland areas seem like a different world, but everything is connected.
